* The purpose of this service is to enable transports to
* traverse NAT routers, by providing traversal options and
* knowledge about the local network topology.
+ *
+ * TODO:
+ * - call GN_start_gnunet_nat_server_() if possible (i.e.
+ * when we find we have a non-global IPv4 address)
+ * - implement autoconfig
+ * - implmeent UPnPC/PMP-based NAT traversal
+ * - implement NEW logic for external IP detection
*/
#include "platform.h"
#include <math.h>
#include "gnunet_statistics_service.h"
#include "gnunet_nat_service.h"
#include "gnunet-service-nat_stun.h"
+#include "gnunet-service-nat_helper.h"
#include "nat.h"
#include <gcrypt.h>
};
+/**
+ * External IP address as given to us via some STUN server.
+ */
+struct StunExternalIP
+{
+ /**
+ * Kept in a DLL.
+ */
+ struct StunExternalIP *next;
+
+ /**
+ * Kept in a DLL.
+ */
+ struct StunExternalIP *prev;
+
+ /**
+ * Task we run to remove this entry when it is stale.
+ */
+ struct GNUNET_SCHEDULER_Task *timeout_task;
+
+ /**
+ * Our external IP address as reported by the
+ * STUN server.
+ */
+ struct sockaddr_in external_addr;
+
+ /**
+ * Address of the reporting STUN server. Used to
+ * detect when a STUN server changes its opinion
+ * to more quickly remove stale results.
+ */
+ struct sockaddr_storage stun_server_addr;
+
+ /**
+ * Number of bytes used in @e stun_server_addr.
+ */
+ size_t stun_server_addr_len;
+};
+
+
+/**
+ * Timeout to use when STUN data is considered stale.
+ */
+static struct GNUNET_TIME_Relative stun_stale_timeout;
+
/**
* Handle to our current configuration.
*/
*/
static struct LocalAddressList *lal_tail;
+/**
+ * Kept in a DLL.
+ */
+static struct StunExternalIP *se_head;
+
+/**
+ * Kept in a DLL.
+ */
+static struct StunExternalIP *se_tail;
+
/**
* Free the DLL starting at #lal_head.
}
+/**
+ * Notify all clients about our external IP address
+ * as reported by the STUN server.
+ *
+ * @param ip the external IP
+ * @param add #GNUNET_YES to add, #GNUNET_NO to remove
+ */
+static void
+notify_clients_stun_change (const struct sockaddr_in *ip,
+ int add)
+{
+ /* FIXME: notify clients about add/drop */
+}
+
+
+/**
+ * Function to be called when we decide that an
+ * external IP address as told to us by a STUN
+ * server has gone stale.
+ *
+ * @param cls the `struct StunExternalIP` to drop
+ */
+static void
+stun_ip_timeout (void *cls)
+{
+ struct StunExternalIP *se = cls;
+
+ se->timeout_task = NULL;
+ notify_clients_stun_change (&se->external_addr,
+ GNUNET_NO);
+ GNUNET_CONTAINER_DLL_remove (se_head,
+ se_tail,
+ se);
+ GNUNET_free (se);
+}
+
+
/**
* Handler for #GNUNET_MESSAGE_TYPE_NAT_HANDLE_STUN message from
* client.
payload_size,
&external_addr))
{
- /* FIXME: do something with "external_addr"! We
- now know that a server at "sa" claims that
+ /* We now know that a server at "sa" claims that
we are visible at IP "external_addr".
We should (for some fixed period of time) tell
(with a sane default), so that the UDP plugin can tell how
often to re-request STUN.
*/
-
+ struct StunExternalIP *se;
+
+ /* Check if we had a prior response from this STUN server */
+ for (se = se_head; NULL != se; se = se->next)
+ {
+ if ( (se->stun_server_addr_len != sa_len) ||
+ (0 != memcmp (sa,
+ &se->stun_server_addr,
+ sa_len)) )
+ continue; /* different STUN server */
+ if (0 != memcmp (&external_addr,
+ &se->external_addr,
+ sizeof (struct sockaddr_in)))
+ {
+ /* external IP changed, update! */
+ notify_clients_stun_change (&se->external_addr,
+ GNUNET_NO);
+ se->external_addr = external_addr;
+ notify_clients_stun_change (&se->external_addr,
+ GNUNET_YES);
+ }
+ /* update timeout */
+ GNUNET_SCHEDULER_cancel (se->timeout_task);
+ se->timeout_task
+ = GNUNET_SCHEDULER_add_delayed (stun_stale_timeout,
+ &stun_ip_timeout,
+ se);
+ return;
+ }
+ /* STUN server is completely new, create fresh entry */
+ se = GNUNET_new (struct StunExternalIP);
+ se->external_addr = external_addr;
+ GNUNET_memcpy (&se->stun_server_addr,
+ sa,
+ sa_len);
+ se->stun_server_addr_len = sa_len;
+ se->timeout_task = GNUNET_SCHEDULER_add_delayed (stun_stale_timeout,
+ &stun_ip_timeout,
+ se);
+ GNUNET_CONTAINER_DLL_insert (se_head,
+ se_tail,
+ se);
+ notify_clients_stun_change (&se->external_addr,
+ GNUNET_NO);
}
GNUNET_SERVICE_client_continue (ch->client);
}
GNUNET_SERVICE_client_drop (ch->client);
return;
}
- /* FIXME: actually run the logic! */
+ /* FIXME: actually run the logic by
+ calling 'GN_request_connection_reversal()' */
GNUNET_SERVICE_client_continue (ch->client);
}
-/**
- * Handler for #GNUNET_MESSAGE_TYPE_NAT_REQUEST_TEST message from
- * client.
- *
- * @param cls client who sent the message
- * @param message the message received
- */
-static void
-handle_test (void *cls,
- const struct GNUNET_NAT_RequestTestMessage *message)
-{
- struct ClientHandle *ch = cls;
-
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Received REQUEST_TEST message from client\n");
- /* FIXME: actually process test request */
- GNUNET_SERVICE_client_continue (ch->client);
-}
-
-
/**
* Check validity of #GNUNET_MESSAGE_TYPE_NAT_REQUEST_AUTO_CFG message
* from client.
static void
shutdown_task (void *cls)
{
+ struct StunExternalIP *se;
+
+ while (NULL != (se = se_head))
+ {
+ GNUNET_CONTAINER_DLL_remove (se_head,
+ se_tail,
+ se);
+ GNUNET_SCHEDULER_cancel (se->timeout_task);
+ GNUNET_free (se);
+ }
if (NULL != scan_task)
{
GNUNET_SCHEDULER_cancel (scan_task);
struct GNUNET_SERVICE_Handle *service)
{
cfg = c;
+ if (GNUNET_OK !=
+ GNUNET_CONFIGURATION_get_value_time (cfg,
+ "NAT",
+ "STUN_STALE",
+ &stun_stale_timeout))
+ stun_stale_timeout = GNUNET_TIME_UNIT_HOURS;
GNUNET_SCHEDULER_add_shutdown (&shutdown_task,
NULL);
stats = GNUNET_STATISTICS_create ("nat",
GNUNET_MESSAGE_TYPE_NAT_REQUEST_CONNECTION_REVERSAL,
struct GNUNET_NAT_RequestConnectionReversalMessage,
NULL),
- GNUNET_MQ_hd_fixed_size (test,
- GNUNET_MESSAGE_TYPE_NAT_REQUEST_TEST,
- struct GNUNET_NAT_RequestTestMessage,
- NULL),
GNUNET_MQ_hd_var_size (autoconfig_request,
GNUNET_MESSAGE_TYPE_NAT_REQUEST_AUTO_CFG,
struct GNUNET_NAT_AutoconfigRequestMessage,
projects / oweals / gnunet.git / blobdiff